Poron provides maximum cushioning for the crucial heel and forefoot areas while being lightweight and durable. The extra deep heel cup helps cushion the foot by utilizing the natural cushioning tissues in the heel of the foot. Air channels molded into the shape of the arch help move warm air out and draw cooler air into the footwear. By controlling the amount the foot slides across the insole's surface, the anti friction top cover helps prevent blisters and keeps feet cooler and drier. Size D